Talk:PostBar

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PostBar is unique to Canada. It is NOT used by Australia Post or the Royal Mail.[edit]

Australia Post and the Royal Mail have their own 4-State barcode systems which are similar but incompatible with Canada's PostBar system.

Only the Canadian barcode scheme is called PostBar.

This specification for PostBar may be incorrect.[edit]

I don't know if this should be included in the PostBar article or just used for discussion.

Unless I am reading them incorrectly, the examples in Canada Post's 4-State Bar Code Handbook are very clearly using an encoding scheme that is different from that described in this article.

For example: the Domestic Barcode Formats given here and in the U.S. Patent 5,602,382 Documentation use 15 bars to encode the six character Postal Code, but the examples in Canada Post's 4-State Bar Code Handbook only use 12 bars. Using the 15 bar 'ANANAN' scheme described in the patent documentation, the Postal Code K1G 3T6 would be coded as PostBarPostalCode K1G3T6 AN Coding.png. Yet in the handbook's example for Domestic Bar Code Format D52.01, the Postal Code for K1G 3T6 is coded as PostBarPostalCode K1G3T6.png . Even more disturbing, examples from both use the same DCI code for two clearly different PostBar formats.

Canada Post's 4-State Bar Code Handbook also mentions the use of the '#' character in PostBar encodings, but this character is not included among the characters given in this article. Also mentioned is a 'D' character encoding, which is probably distinct from the 'Z', 'A', 'B', and 'N' encodings given here.

One, and only one, of the examples included in Canada Post's 4-State Bar Code Handbook does use the 'Z' character encoding described in this article. It is for the S82.39 structure. However, it uses a DCI composed of a Descender, an Ascender, and a Tracker (PostBarDCI S82 39.png), which corresponds to no character described in this article, and therefore certainly does not fall in the range of M - U as written in this article. This example from the handbook also uses a Bar Code Sequencer field, which is not described in either the handbook or in this article.

Unlike the United States Postal Service's POSTNET and PLANET barcode standards, or Australia's own 4-State postal bar code system, or the 4-State bar code system used by the Royal Mail, the Canada Post PostBar Specification is not open. For reasons understood only by itself, Canada Post requires a signed license and a hefty fee before anyone is allowed to print and mail with PostBar codes, or even learn the actual PostBar specification. It is unclear why Canada Post has decided to make it difficult and expensive for their customers to implement the PostBar system for automated mail sorting. This policy certainly seems counter productive to their purported goal of speeding the mail with maximum efficiency.

Regardless of their reasons, the tight lid Canada Post has kept on the PostBar specification has meant its almost compete lack of adoption across Canada. While the Unites States Postal Service's POSTNET codes can be easily generated using fairly ubiquitous software like MicroSoft Word, Canada Post's PostBar codes can only be generated using a small set of obscure and expensive software packages. The resulting scarcity of PostBar coded mailings in Canada means there is a limited sample set of correctly formatted bar codes available for proper "clean room" reverse engineering the actual PostBar specification as implemented in a way that is unencumbered by Canada Post's expensive and restrictive license requirements.

Until Canada Post changes their policy or someone successfully reverse engineers the PostBar encoding system as it is actually implemented, it is doubtfull it will ever see wide usage and the average Canadian postal customer will continue to rely on less accurate and slower OCR and hand sorted mail.

PillboxGirl 08:46, 9 January 2006 (UTC)

Examples of Canada Post's 4 state bar codes for Decryption/Reverse Engineering[edit]

From a PC World Magazine Subscription Card: http://img490.imageshack.us/img490/858/dsc02825au2.jpg --Mozillaman 23:27, 13 January 2007 (UTC)

And another: http://img296.imageshack.us/img296/5918/docpd6babbc87c80dfcde2eho8.jpg --Mozillaman 23:27, 13 January 2007 (UTC)

12-bar postal code encoding[edit]

The 12-bar postal codes consist of 3 groups with 4 bars each. To decode, convert the barcode to a base-4 number as specified in section 3.1.2 of the handbook, then convert each group of 4 digits to a decimal value. For example, K1 G3 T6 encodes as PostBarPostalCode K1G3T6.png, which is 1123 0333 2322 in base 4, or 091 063 186 in decimal. The last decimal digit of each group gives the number (1, 3, 6). The first two digits specify the letter, where I guess 00=A, 01=B, ..., 07=H, 08=J (note that "I" was skipped), 09=K, ..., 24=Z. The meaning of 250-255 is unknown.

There are 3 good examples in the handbook: K1G3T6, K1S1B9, L3B4T9. The codes shown with N6G3R7 and L5N6L5 seem bogus. The encoding of letters B(01), G(06), K(09), L(10), S(17), T(18) match barcodes given in the guide, and I've also confirmed J(08) on real mail. I'm just assuming the others match this pattern.

The sample images linked from the above comment show business reply mail, which doesn't seem to be encoded this way (note also that the postal code printed above each barcode doesn't match that shown in the address field). I've also seen residential mail that appears to be encoded differently. More examples of barcodes (especially residential ones) would be useful.

Chwells (talk) 23:07, 17 September 2008 (UTC)

Australia Post Address barcode[edit]

For details, see the section entitled The 4-State Barcode on the Australia Post website's Barcoding Library page. --AlastairIrvine 04:47, 29 October 2007 (UTC)

How is it Scanned?[edit]

No info in the article about how this barcode format is actually scanned, which would be informative. It has multiple bar heights, so a standard scanner wouldn't work. Do PostBar scanners use a series of three standard photosensors arranged vertically, just one that sweeps on two axes, a QR-code-like camera sensor, or something else? 174.20.78.181 (talk) 20:26, 9 March 2017 (UTC)